The Fifth Scientific Meeting of The TMJ Association, Can Studies of Co-Morbidities with TMJDs Reveal Common Mechanisms of Disease?, is scheduled to be held in May/June 2008 at the Federation of American Societies for Experimental Biology Center in Bethesda, Maryland. The need for this meeting and that of previous meetings has been based on two important factors. First, the number of people affected by temporomandibular joint and muscle disorders (TMJDs) is estimated to be more than 10 million in the United States. Ninety percent are women in their childbearing years. The physical, psychological and financial burden on these patients is compelling. Second, there continues to be a dearth of scientific understanding of the etiology of these conditions upon which to base diagnosis and develop safe and effective treatments. To stimulate research in this field, The TMJ Association has organized biennial scientific meetings beginning in the year 2000. These meetings have convened experts from TMJDs and other fields to characterize and address the multiple symptoms and co-morbid conditions found in TMJD patients. The theme of the fifth scientific meeting builds upon evidence from the four previous meetings showing that TMJDs are a complex family of conditions influenced by genetics, gender, environmental and behavioral triggers mediating the vulnerability of patients to TMJDs and manifesting as more than jaw and muscle pain and jaw dysfunction. The 2008 proposed meeting will bring together clinical and basic scientists who have made advances in the diagnosis and treatment of TMJDs with scientists knowledgeable about other chronic pain conditions such as chronic headache, generalized pain conditions, irritable bowel syndrome, fibromyalgia, low back pain, chronic fatigue syndrome, and rheumatoid arthritis with which TMJD patients frequently share common symptoms. The Specific Aims of the proposed meeting are to: 1) identify similarities across these diseases, perhaps finding common pathways that could elucidate the underlying pathophysiology of TMJDs and point to novel targets for diagnosis and treatment; 2) promote and engage new and young investigators in TMJD research; and 3) develop recommendations for research initiatives in TMJDs that would synergize the work scientists at multiple Institutes and Centers of the National Institutes of Health and that of Academic Health Centers. Project Narrative: The variety of current treatments for Temporomandibular Joint and Muscle Disorders (TMJDs) lack a coherent body of scientific knowledge. It is imperative that the underlying pathophysiological processes that drive these conditions are understood in order to provide accurate and predictable diagnostics and safe and effective therapies. This scientific meeting brings together clinical and basic scientists together with patients to consider common underlying mechanisms that may be responsible for TMJDs and other shared co-morbidities, as are seen in chronic headache, generalized pain conditions, irritable bowel syndrome, fibromyalgia, low back pain, chronic fatigue syndrome, and rheumatoid arthritis. A major goal of this meeting is to identify common therapeutic targets related to shared co-morbidities. [unreadable] [unreadable] [unreadable]